It is a genetic disorder that affects nerves, muscles, other organs, and behavior. Metachromatic leukodystrophy slowly gets worse over time. MLD is a severe disease that gets worse over time. In time people lose all muscle and mental function. A person with MLD has a life span that varies depending on what age the condition started. The disease course usually runs 3 - 20 or more years. People with this disorder are expected to have a shorter-than-normal lifespan. The disease progresses quicker when diagnosed at an early age. This is inherited from parents. Children with parents that both have a defective gene will have a 25% chance of having metachromatic leukodystrophy. MLD occurs in about 1 in 40,000 people. There are three forms of the disease: Late infantile MLD, Juvenile MLD, and Adult (and late-stage juvenile MLD). They are based on when the symptoms begin.
Late infantile MLD:
symptoms usually begin by ages 1 - 2
Symptoms include muscle wasting and weakness, muscle rigidity, developmental delays, progressive loss of vision leading to blindness, convulsions, impaired swallowing, paralysis, and deme
the most common form of MLD
affected children begin having difficulty walking after the first year of life, usually at 15–24 months.
Children may become comatose. Untreated, most children with this form of MLD die by age 5, often much sooner.
Juvenile MLD:
symptoms usually begin between ages 4 and 12.
symptoms similar to the late infantile form but with slower progression
usually begin with impaired school performance, mental deterioration, and dementia and then develop
Age of death is variable
but normally within 10 to 15 years of symptom onset although some juveniles can live for several decades or longer after onset.
Adult ( late stage juvenile MLD ):
symptoms may occur between age 14 and adulthood (over age 16), but may begin as late as the 40s or 50s.
begins after age 16 as a psychiatric disorder or progressive dem
entia
Adult-onset MLD progresses more slowly than the late infantile and juvenile forms, with a protracted course of a decade or more
Definition of the name
meta - change chromatic - color leuko - white matter dystrophy - degeneration Metachromatic leukodystrophy is also known as MLD. MLD's name therefore comes from degeneration in the white matter of the brain and Central Nervous System (CNS) which has a color on staining that should not be there. Staining was how the disease was observed before the advent of the MRI.
Molecular Basis:
This disease is also known as Arylsulfatase A deficiency. People who have this are lacking an enzyme called arylsulfatase. Without this enzyme, chemicals know as sulfatides build-up in the white matter of the brain because they are not broken down. It damages the nervous system, kidneys, gallbladder, and other organs. It causes destruction of the myelin sheath, or demyelination. The chemicals basically damage the protective sheaths that surround nerve cells. With a damaged myelin sheath there is a breakdown in communication between the nerves and the brain. This loss of or miscommunication accounts for the loss of acquired functions, paralysis, blindness, seizures and eventual death seen in MLD.
Table of Contents
Metachromatic leukodystrophy (MLD)
By: Shenell
What is metachromatic leukodystrophy?
It is a genetic disorder that affects nerves, muscles, other organs, and behavior. Metachromatic leukodystrophy slowly gets worse over time. MLD is a severe disease that gets worse over time. In time people lose all muscle and mental function. A person with MLD has a life span that varies depending on what age the condition started. The disease course usually runs 3 - 20 or more years. People with this disorder are expected to have a shorter-than-normal lifespan. The disease progresses quicker when diagnosed at an early age.Late infantile MLD:
Juvenile MLD:
Adult ( late stage juvenile MLD ):
entia
Definition of the name
meta - changechromatic - color
leuko - white matter
dystrophy - degeneration
Metachromatic leukodystrophy is also known as MLD. MLD's name therefore comes from degeneration in the white matter of the brain and Central Nervous System (CNS) which has a color on staining that should not be there. Staining was how the disease was observed before the advent of the MRI.
Molecular Basis:
This disease is also known as Arylsulfatase A deficiency. People who have this are lacking an enzyme called arylsulfatase. Without this enzyme, chemicals know as sulfatides build-up in the white matter of the brain because they are not broken down. It damages the nervous system, kidneys, gallbladder, and other organs. It causes destruction of the myelin sheath, or demyelination. The chemicals basically damage the protective sheaths that surround nerve cells. With a damaged myelin sheath there is a breakdown in communication between the nerves and the brain. This loss of or miscommunication accounts for the loss of acquired functions, paralysis, blindness, seizures and eventual death seen in MLD.Videos about Metachromatic leukodystrophy:
https://www.youtube.com/watch?v=X8XWeT0QrhA
https://www.youtube.com/watch?v=UJE77-UQwKg
Hyperlinks:
http://www.nlm.nih.gov/medlineplus/ency/article/001205.htm
http://mldfoundation.org/MLD-101-what.html
http://en.wikipedia.org/wiki/Metachromatic_leukodystrophy